Blankenstein Castle was built originally in 1227-1243 by Adolf I, Count of Mark. It was further developed over the course of 200 years by the Counts of the Mark. By 1425, Blankenstein was one of the most important castles in the county. In 1614, shortly before the Thirty Years' War, it was occupied by Spanish troops. From 1637, the castle fell into disrepair so that, in September 1662, Frederick William, Elector of Brandenburg ordered its demolition. Only the tower and parts of the curtain wall remained.
In 1860, the owner of the ruin, the employer, Gustav vom Stein, began to rebuild the castle and established a factory there. The property has belonged to the city of Bochum since 1922, but the town is looking for an alternative due to the costs. From 1957 to 1959, most of the buildings of the 19th century were pulled down, but some still remain.
The tower can still be visited and offers a good view over Bochum and the Kemnader Lake.
References:Střekov Castle (Schreckenstein) is perched atop a cliff above the River Elbe, near the city of Ústí nad Labem. It was built in 1316 for John of Luxembourg, the father of the Holy Roman Emperor Charles IV, to guard an important trade route to Germany. After changing hands several times, the castle was acquired by the Lobkowicz family in 1563. Its strategic importance led to occupations by Imperial Habsburg, Saxon, and Swedish forces during the Thirty Years' War, as well as successive sieges by Austrian and Prussian armies during the Seven Years' War.
Although Střekov Castle was heavily damaged during those conflicts and abandoned as a military installation by the end of the 18th century, the 1800s saw many poets and artists visiting the castle, drawn by a new trend of interest in romantic ruins.